Vertical localization between devices using altitude measurements

Abstract

In some implementations, the techniques may include at a first time: performing, using a first sensor, a first ranging measurement with a second device to obtain a first distance; and performing, using a second sensor, a first altitude measurement to obtain a first altitude. In addition, the techniques may include at a second time: performing, using the first sensor, a second ranging measurement with the second device to obtain a second distance; and performing, using the second sensor, a second altitude measurement to obtain a second altitude. The techniques may include determining a ranging difference between the first distance and the second distance. Moreover, the techniques may include determining an altitude difference between the first altitude and the second altitude. Also, the techniques may include determining whether the second device is on a different floor of a building than the first device.

What is claimed is: 
     
         1 . A method comprising performing, by a first device:
 at a first time:
 performing, using a first sensor, a first ranging measurement with a second device to obtain a first distance; and 
 performing, using a second sensor, a first altitude measurement to obtain a first altitude; 
   at a second time:
 performing, using the first sensor, a second ranging measurement with the second device to obtain a second distance; and 
 performing, using the second sensor, a second altitude measurement to obtain a second altitude; 
   determining a ranging difference between the first distance and the second distance; and   determining an altitude difference between the first altitude and the second altitude.   
     
     
         2 . The method of  claim 1 , further comprising:
 determining whether the second device is on a different floor of a building than the first device.   
     
     
         3 . The method of  claim 2 , further comprising:
 displaying a notification on a display of the first device, the notification indicating that the second device is on the different floor of the building than the first device.   
     
     
         4 . The method of  claim 2 , wherein determining whether the second device is on the different floor comprises:
 comparing the altitude difference to a threshold; and   determining that the second device is on a different floor of the building in response to the altitude difference exceeding the threshold.   
     
     
         5 . The method of  claim 2 , wherein determining whether the second device is on the different floor comprises:
 comparing the ranging difference to a threshold; and   determining that the second device is on a different floor of the building in response to the ranging difference exceeding the threshold.   
     
     
         6 . The method of  claim 1 , wherein determining the first altitude measurement comprises:
 performing a first air pressure measurement using the second sensor; and   calculating the first altitude measurement based on the first air pressure measurement.   
     
     
         7 . The method of  claim 6 , wherein determining the altitude difference comprises:
 subtracting a second air pressure reading corresponding to the second altitude measurement from the first air pressure measurement to calculate the altitude difference.   
     
     
         8 . A computing device, comprising:
 one or more memories; and   one or more processors in communication with the one or more memories and configured to execute instructions stored in the one or more memories to performing operations to:   at a first time:
 perform, using a first sensor, a first ranging measurement with a second device to obtain a first distance; and 
 perform, using a second sensor, a first altitude measurement to obtain a first altitude; 
   at a second time:
 perform, using the first sensor, a second ranging measurement with the second device to obtain a second distance; and 
 perform, using the second sensor, a second altitude measurement to obtain a second altitude; 
   determine a ranging difference between the first distance and the second distance; and   determine an altitude difference between the first altitude and the second altitude.   
     
     
         9 . The computing device of  claim 8 , further comprising operations to:
 determine whether the second device is on a different floor of a building than the computing device.   
     
     
         10 . The computing device of  claim 9 , further comprising operations to:
 display a notification on a display of the computing device, the notification indicating that the second device is on the different floor of the building than the computing device.   
     
     
         11 . The computing device of  claim 9 , wherein determining whether the second device is on the different floor comprises operations to:
 compare the altitude difference to a threshold; and   determine that the second device is on a different floor of the building in response to the altitude difference exceeding the threshold.   
     
     
         12 . The computing device of  claim 9 , wherein determining whether the second device is on the different floor comprises operations to:
 compare the ranging difference to a threshold; and   determine that the second device is on a different floor of the building in response to the ranging difference exceeding the threshold.   
     
     
         13 . The computing device of  claim 8 , wherein determining the first altitude measurement comprises operations to:
 perform a first air pressure measurement using the second sensor; and   calculate the first altitude measurement based on the first air pressure measurement.   
     
     
         14 . The computing device of  claim 13 , wherein determining the altitude difference comprises operations to:
 subtract a second air pressure reading corresponding to the second altitude measurement from the first air pressure measurement to calculate the altitude difference.   
     
     
         15 . A computer-readable medium storing a plurality of instructions that, when executed by one or more processors of a computing device, cause the one or more processors to perform operations to:
 at a first time:
 perform, using a first sensor, a first ranging measurement with a second device to obtain a first distance; and 
 perform, using a second sensor, a first altitude measurement to obtain a first altitude; 
   at a second time:
 perform, using the first sensor, a second ranging measurement with the second device to obtain a second distance; and 
 perform, using the second sensor, a second altitude measurement to obtain a second altitude; 
   determine a ranging difference between the first distance and the second distance; and   determine an altitude difference between the first altitude and the second altitude.   
     
     
         16 . The computer-readable medium of  claim 15 , further comprising operations to:
 determine whether the second device is on a different floor of a building than the computing device.   
     
     
         17 . The computer-readable medium of  claim 16 , further comprising operations to:
 display a notification on a display of the computing device, the notification indicating that the second device is on the different floor of the building than the computing device.   
     
     
         18 . The computing device of  claim 16 , wherein determining whether the second device is on the different floor comprises operations to:
 compare the altitude difference to a threshold; and   determine that the second device is on a different floor of the building in response to the altitude difference exceeding the threshold.   
     
     
         19 . The computer-readable medium of  claim 16 , wherein determining whether the second device is on the different floor comprises operations to:
 compare the ranging difference to a threshold; and   determine that the second device is on a different floor of the building in response to the ranging difference exceeding the threshold.   
     
     
         20 . The computer-readable medium of  claim 15 , wherein determining the first altitude measurement comprises operations to:
 perform a first air pressure measurement using the second sensor; and   calculate the first altitude measurement based on the first air pressure measurement.